MULTIVARIATE ANALYSIS FOR INDEPENDENT VARIABLE SCREENING IN THE DEVELOPMENT OF PROTEIN GEL AS A SUBSTITUTE FOR ANIMAL FAT

The consumption of saturated fats can be associated with chronic diseases, making it an alternative to replace animal fat with protein gels. The objective of this study was to develop a protein gel and use the Plackett-Burman design to select the independent variables with the greatest influence on the technological functional properties of the gel. The independent variables used included pea protein, soy protein, albumin, and whey protein (3-7 %), agar and a mixture of carboxymethyl cellulose with carrageenan in a ratio of 25:75 to 75:25, respectively (0.5-1.5 %), NaCl, CaCl2, KCl, and MgCl2 (0.1-1.1), pH (3.5-7.5), and temperature (45-85), using a PB20 design with 4 central points (R2>0.75; P<0.10). To prepare the gels, the ingredients were mixed, homogenized, and the pH adjusted with NaHCO3 or citric acid and then heated in a water bath until reached the defined temperature. The gel was poured into plastic containers and stored at 4°C for 24 hours. The color parameters of the gels were affected by changes in pH, pea protein, soy protein, and temperature (R2 equal to 0,7796 to L*, 0.8664 to a* and 0.9057 to b*). Water activity was reduced by pH and temperature (R2 = 0.8329). Water retention capacity was increased by soy protein, pea protein, albumin, temperature, and CaCl2 (R2 = 0.9787). Texture parameters were influenced by pea protein, soy protein, albumin, temperature, CaCl2, carrageenan, carboxymethyl cellulose, and agar (0.7529<R2<0.9706). Based on these results, pea protein, soy protein, and albumin were the variables that had the most significant impact on gel properties, with the potential for further exploration in studies aimed at determining the best protein concentration and proportion to enhance the functional properties of protein gels.